How is Sulphur Estimated by the Carius Method?

Answer: The Carius method involves heating a known mass of an organic substance that also contains sulphur in the presence of excessive fuming nitric acid inside a sealed Carius tube. This organic molecule undergoes a chemical reaction that produces sulphuric acid from the element sulphur. An excessive amount of barium chloride solution is used to neutralise this sulphuric acid. The formation of barium sulphate is followed by its subsequent precipitation. After that, it is weighed, rinsed, and filtered to remove any impurities. This percentage represents the amount of sulphur. As a result, we refer to this procedure as the “estimation of sulphur using the Carius method.”